Julian, it's equally easy to run the cord down your front -- that's what I do when I'm commuting. Before you put the phones in, slide the clear tube down to the bottom, hold the cord in front of you, bring the phones up along the line of your jaw, then coil the cord around your ears from behind and insert the phones. Then just slide the clear tube up to tighten the cord under your chin.
I had a hard time figuring out how to put the cord down the back, because I started out with the in-front position. I think the problem is that you can't switch from one position to the other without taking out the phones entirely, so you can't stumble on the alternate arrangement by accident.
